Department of Electrical and Computer Engineering


Forensics and biometrics

Forensics and Biometrics (FaB) is concerned with advancing the state of the art in signal processing methods and technologies as they are used in the fields of forensic and biometric analysis.

Forensic and biometric signal processing are related, in that both fields attempt to infer information about an underlying subject based on measured, but incomplete, data samples. Our specific areas of academic interest include image and acoustic forensics, image and acoustic biometrics, acoustic analysis as it pertains to human physiology and numerous tangential applications of these methods.

Research


Human Biometrics

Human biometrics is the automated recognition of a person using inherent, distinctive physiological or involuntary behavioural features. Example biometrics include speech, lips, fingerprints, irises, and gait. Our goal is to develop new algorithms to process unique biometric features extracted from different body parts.

Given the limitations of using a single biometric measure, we are attempting to improve the robustness and reliability of recognition by fusing multiple biometric measurements. For example, a hand is placed over a suitable sensor and features such as vein pattern and palm geometry are extracted for classification purposes. These two biometric features are then fused either in the feature domain or the classification domain to improve recognition performance.

Biometric-enabled systems are very much application-dependent so we need to investigate and develop expertise in many biometrics to best match the set of biometrics to a given application. For health applications, we need to consider non-contact sensors for hygienic purposes. Speech and palm vein patterns are ideal biometrics that comply with the non-contact requirement.

A long-term goal is the discovery and development of new biometric features.

Forensic Image Processing via Hyperspectral Methods

Hyperspectral images differ from regular pictures in that each pixel contains a spectrum of light over some portion of the optical spectrum. Typically that includes the visible and near infrared spectrum from approximately 400 nm to 1200 nm. One of our goals is to exploit the extra information available in hyperspectral images with a long-term plan to develop prototype tools to aid law enforcement professionals when examining a crime scene.

For example, we are developing the components of a hyperspectral crime scene camera that can identify candidate substances of possible forensic interest based on the spectral reflectance properties of the scene. The aim is for this to be achieved without contact with any material at the scene. This sort of work requires theoretical advances in algorithm development and signal representation as well as innovative hardware designs to make future devices portable and useful in the field.

Parallel research projects using hyperspectral methods include the development of highly robust skin detection methods for occupational safety; an iris recognition system integrating spectral and spatial information; and using multispectral data to aid in the automated processing of fresh produce.

We are actively looking for new applications of hyperspectral image processing techniques.

Modelling Speech Production

We are currently modelling the impact that aging has on speech production. Our studies focus on both the speech signal and models of the speech production system. To date our major focus has been on the vocal tract and the related acoustics. We have an acoustic reflectometer to measure vocal tract shapes and have obtained precise MRI measurements of the vocal tract shapes. From these shapes we can derive the resulting acoustic signal. The models can be improved with knowledge of the speech source and recently we have acquired a Laryngograph to measure glottal pulses. Applications of this work include speaker identification, speech recognition, speech synthesis, speech forensics (see below) and vocal health.

We also are developing synthetic voices for robots and have recently developed a synthetic New Zealand English Voice.

Speech Forensics

For many years the courts have made extensive use of recordings of conversations of offenders and suspects. Frequently these are covertly acquired via hidden listening devices or by evesdropping on telephone and mobile communications. One common feature of such recordings is their very poor recording quality which makes subsequent determination of both content and speaker identity very challenging.

We have expertise in forensic speech analysis and are currently investigating the impact of cell phone technology on the acoustic parameters associated with speech that are important to the task of speaker identification in forensic applications.

General Speech and Audio Processing

We are also active in processing and modelling speech and audio signals for several applications such as audio watermarking, noise reduction and echo cancellation, speech recognition, speaker localisation, active noise control, automatic music assessment, music processing, and speaker recognition. A recently developed audio watermarking system is ready for commercial deployment.

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Students


Contact


Dr Catherine Watson
Phone: + 64 9 3737 599 ext 85979
Email: c.watson@auckland.ac.nz

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Current postgraduates

Research topic

Programme

Name

Year

Towards a hyperspectral forensic crime-scene camera

PhD

Robert Dunn

2010

Fingerprint multispectral and vein imaging as human biometrics

PhD 

Maja Krivokuca

2010

Automatic face analysis to imitate human visual perception

PhD

Vedrana Krivokuca

2010

Acoustic echo cancellation and ambient noise reduction for radio communications

PhD

Matthew McCallum

2010

Determination and display of spatial and temporal room impulse responses

ME

Daniel Protheroe

2010

Simulating the effects of aging on the larynx using acoustic and physiological models

PhD

Stephen Bier

2009

Synthetic speech for a healthcare robot: investigation, issues, and implentation

ME

Aleksandar Igic

2009

Towards real-time hyperspectral processing

ME

Reymond Takashima

2009

Speech recognition for computer aided pronunciation systems

ME

Xu Xie

2009
Hyperspectral iris recognition

PhD

Robert Bowmaker 2008
Multispectral imaging of fresh produce

PhD

Kenneth Moynihan 2008
Hyperspectral skin detection for occupational safety

PhD

Timothy Roper 2008
Hearing enhancement in noisy environments by active noise control

PhD

Iman Tabatabaei Ardekani 2008

Development of a rhythm metric for the anlaysis of mora- and stress-timed language and its application to sound change in Maori

PhD

Laura Thompson 2008
Applications of hyperspectral imaging techniques to forensic image analysis

PhD

Shaun Dowler 2005
Gait analysis for human identification

PhD

Neel Pandy 2005

On the transformation of accent

PhD

Jono Teutenberg 2005



 

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Past postgraduates


Research topic

Programme

Name

Year

Robust audio watermarking for digital media copyrights protection

PhD

Tina Yiqing Lin

2010

Speech enhancement using a small microphone array

PhD

Qingning Zeng

2010

Embedded speech recognition system

PhD

Octavian Cheng

2009

Multi-agent based ambient intelligence platform

PhD

Kevin I-Kai Wang

2009

Quantitative continuity feature for preterm neonatal EEG signal analysis

PhD

Lisa Wong

2009

Speaker identification using microphone arrays

PhD

Yushi Zang

2009

An investigation into perceptual audi coding and the use of auditory gammatone filterbank

ME

Andrew Chen-Yang Lin

2007

Real-time digital image sequence stabilisation

ME

Mark Weir

2006

Detection and characterisation of cracks and defects in carbon anodes

ME

David Hirschfeld

2005

Speech enhancement using microphone array

ME

Peng Sun

2005

Acoustic and articulatory consequences of hypo- and hyper-articulation

PhD

Zoe Evans

2004

Real-time saw blade deflection monitoring using laser triangulation sensor and FPGA

ME

Joanna Cheuk Kuen Lai

2004

Point particle reconstruction from a limited number of projections

ME

Nicholas Ling Chun Mok

2004

Sound source localisation using microphone arrays

ME

Gary Wai-Yin Sin

2004

Voice print for speaker recognition

ME

Chow Chi Tak

2004

Particle filter lips tracker for visual speaker verification

ME

Paul Wai Tak Yu

2004

A prototype algorithm for optical recognition of embossed braille

ME

Lisa Wong

2004

Quantitative near-infrared imaging spectroscopy of fruit

PhD

Paul Martinsen

1999

Fractional differintegration and its digital implementation

ME

Feng Jia

1999

A personal computer-based symbolic analogue network analyzer (SANA)

ME

Made Gunawan

1998

Coupling scintillation light into optical fibre for use in a combined positron-emission tomography and magnetic resonance imaging scanner

ME

Gerhard Haak

1997

High resolution image reconstruction by stochastic optimisation

PhD

Thanachart Numnonda

1995

Time-frequency analysis of transient evoked otoacoustic emissions

ME

John Leber

1995

The application of adaptive techniques to duct active noise control

PhD

Mark Johnson

1992

Speech analysis based on a parametric model of the vocal tract and its excitation

PhD

Mark Thomson

1991

Design and analysis of transformer protection algorithms using recursive system identification techniques

ME

Delwyn Moller

1991

The design of two-dimensional recursive filters

ME

Tendy The

1991

Computer restoration and enhancement of half-tone images

ME

Jorg Seibel

1990

Neural networks and their application to speech recognition

ME

Jane Yew Bian Ooi

1990

Speaker recognition based upon an analysis of vowel sounds and its application to forensic work

ME

Michael Miles

1989



 

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